Cleansing means for rock drills



July 31, 1928.

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s 8 S m n I R ay D W0 aw J Am H Am R awn md JGH HF S N A E L C NH //n/ 7 K M I L latented July 31, 1928.

UNITED STATES vra r zn'r orrica;

JAMES G. GRAHAM, OF BUTTE, 'MONTANA, ASSIGNOR TO SULLIVAN MAG HINI JRY COMPANY, A CORPORATION OF MASSACHUSETTS.

CLEANSING MEANS FoanooK 'DRILLSi.

Application filed July 25,

This invention relates to percussive tools and particularly to percussive rock drills of the type employing a longitudinally extending tube for supplying water or other cleansing fluid to a hollow drill steel.

In the operation of tools of this type, considerable ditliculty has been encountered by reason of damage to or complete destruction of the forward end of the cleansing fluid supply tube, which is of relatively lightconstruction, when the drill steel is inserted in the tool. This trouble is sometimes caused by the presence of cuttings or other obstructions which may have become lodged in the rear or inner end of the bore of the drill steel and which, when the steel is inserted, prevent the proper inte-rengagement of the tube and steel, causing the end of the tube to be crushed, bent over, broken off, or otherwise damaged. In other instances, where the hole in the drill steel isnot inperfect alinement with the tube, the latter will, upon the insertion of the drill steel, be slightly deflected at its end so that, when another steel is inserted, it will not properly register therewith and will be damaged thereby.

The present invention has for itsobject to provide cleansing fluid supply means for drills of this type of such a character as not to be injured in the manner above referred to, thereby obviating thedifliculty in ques tion, materially reducingthe cost of operation of such drills, and avoiding the expensive and annoying delays incidental to the repairing of damaged'tools.

The foregoing and other objects of my invention, together with means whereby the same may be carried into eifect,'will best be understood from the following description of one form or embodiment thereof illustrated in the accompanying drawings, in which:

Fig. 1 is a side elevation, partly in section and partly broken away, of a complete rock drilling tool embodying the invention. 7

Fig. 2 is an enlarged longitudinal section of the head block and associated parts, showing in detail the mounting of the rear end of the air and water tubes.

In 1 of the drawings is conventionally illustrated a percussive rock drilling tool.

comprising a motor cylinder 10 having in its forward end a chuck 11 for the usual hollow 1921. serial No. 487,442.

drill" steel 12, said cylinder containing the usual hammer piston 13 adapted, upon its forward move1nent,'to strike the usual anvil block 14 through which the impactis transmit-ted to the rear end of the drill steel 12. The rear end of the cylinder 10 is closed by a head block 15' carrying at its side opposite said motor cylinder the usual feed cylinder 16 containing the feed piston 17. The head block 15 may be of any suitable or usual construction, either unitary or eoinposite,a twopart head block being shown for purposes of illustration. Said head block isprovided withthe usual combined lubricating valve and hand grip 18 and with the valve or valves for controlling the supply of motive I and cleansing fluids to the several parts of the tool. in the construction shown, there is employed a valve bushing 19 containing a I rotary valve 20, compressed air or other mosaid tubes are concentrically disposed and extend longitudinally and concentrically through the piston 18 to the anvil block 14.

In accordance with the present invention, the tube 22 terminates at its forward end Within the anvil block 14, so as to have said forward end enclosed by said anvil block and protected thereby against accidental injury by the drill steel. The water tube 23 projects for a short distance beyond the forward end of the anvil. block 14; and into a position to enter the bore of the drill steel when the latter is fully inserted and its rear or inner end'brought into engagement with said anvil block. At its rear end the air tube 22 is rigidly mounted in a counterbored portion of a gland24l which seated in a centralrecess inv the head bl ck 15, suitable packing 25 being interposed between the forward end of said gland. and the bottom of said recess. The gland'2a is held in position in the head block by a threaded gland to their general construction, 'arrangement,

and function, are well known in tools of this type and require no further description in detail.

The water tube 23, which is also carried by the gland 24, is, in accordance with the present invention, mounted for longitudinal movement in said gland, being normally yieldingly held in its foremost position, and with a flange 28 formed on the inner end thereof in engagement with a countersunk recess at the rear end of said gland, by means of a spring 29 located in an axial bore or chamber 30 formed in the plug 26, being interposed between the flange 28 and a disk of wire gauze or other foraminous material 31 secured, as by upsetting the edges of said plug, at the outer end of the chamber 30. Said chamber 30 is of suiiicient diameter to permit movement of the flange 28 longitudinally therein, and is of a length equal to or slightly greater than the portion of the tube 23 which projects beyond the forward end of the anvil block 1% when said flange 28 is seated upon the end of the gland 24:.

From the foregoing it will be seen that, should the forward end of the water tube 23 fail properly to enter the bore of the drill steel when the latter is inserted, said tube will yield longitudinally and thereby avoid injury, the amount of longitudinal move ment permitted said tube being at least equal to the extent of normal projection of the forward end of said tube beyond the anvil block 14, and therefore sufficient to permit the rear end of the drill steel to engage said anvil. block (which serves as a stop to limit the rearward movement of said steel) without crushing said tube. It will therefore be seen that all danger of mashing, bending, or breaking the forward end of the tube, due to obstruction or malformation of the drill steel, will be prevented. Any obstruction to the drill steel will be immediately dis covered by the operator due to the fact that the water supply through the tube 23, being unable to pass through said drill steel, will escape around the chuck 11 and thereby serve as a warning of the improper operation of the tool.

A r and water may be supplied to the tubes 22 and 23, respectively, in any suitable manner. As herein shown, air from the interior of the valve 20 is admitted through suitable ports and passages 32 in the bushing 19 and valve 20 and passages 33 in the head block 15 to a chamber 34 in the latter, said chamber communicating through ports 35 in the gland 2st with the interior bore thereof. and thence with the tube 22. Water is supplied from the hose connection 21 through suitable ports and passages 36 in the bushing 19 and valve 20 and a passage 37 in the head block 15 to the interior of the cap 2?", whence it flows through the disk 81 to the chamber 30 and thence to the water tube 23.

construct-ion above described and shown in the drawings has been chosen for illustrative purposes merely, and that the invention may be otherwise embodied and practiced without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is 1. In a drilling mechanism, the combination with means: for detachably holding a hollow drill steel and means for operating upon said steel, of a longitudinally disposed tube normally adapted to be telescopically received freely into the bore of said steel for supplying cleansing fluid to the latter, a head block, and a gland carried by said head block and in which the rear end of said tube is supported for longitudinal movement in the event of endwise engagement of the tube by a steel.

2. In a drilling mechanism, the combination with means for detachably holding a hollow drill steel and means for operating upon said steel, of a longitudinally disposed tube normally adapted to be telescopically received freely'into the bore of said steel for supplying cleansing fluid to the latter, a head block, a gland carried by said head block and in which. the rear end of said tube is supported for longitudinal movement in the event of endwise engagement of the tube by a steel, and a gland plug having a chamber disposed in alinement with said tube and into which the rear end of said tube is movable.

3. In a drilling mechanism, the combination with means for detachably holding a hollow drill steel and means for operating upon said steel, of a plurality of concentic longitudinally disposed tubes for supplying cleansing fluids to said drill steel, and ahead block in which the rear end of one of said tubes is rigidly mounted, the rear end of the other of said tubes being mounted for longitudinal movement in said head block in the event of endwise engagement of the tube by a steel and the other end normally adapted to have free telescopic relation with said steel.

4. In a drilling mechanism, a combination with means for detachably holding a hollow drill steel and means for operating upon saiddrill steel, of inner and outer concentrio longitudinally disposed tubes for supplying cleansing fluids to said drill steel, a

wise thrust is impartedto the outer end of said tube and the other end normally adapted to have free telescopic relation with said steel.

5. In a drilling mechanism, the combination wit-h means for detachably holding a hollow drill steel and means: for operating upon said drill steel, of a movably mounted tube normally adapted to telescopefreely a substantial distance into the bore of said steel for supplying cleansing fluid to the latter, and constantly operative means for yieldingly holding said tube in operative position whereby the tube may move axially in the event of endwise engagement by a steel.

6. In a drilling mechanism, the combination with means for detachably holding a hollow drill steel and means for operating upon said steel, of a longitudinally disposed tube for supplying cleansing fluid to said drill steel, a head block, a gland carried by said head block and in which the rear end of said tube is supported for longitudinal movement, a gland plug having a chamber in alinement with said tube and into which the rear end of said tube is longitudinally movable, and a spring in said chamber for normally forcing said tube forwardly.

7. In a drilling mechanism, the combina tion with means for detachably holding a hollow drill steel and means for operating upon said steel, of a stop for said drill steel, a tube for supplying cleansing fluid to said drill steel, said tube normally extending freely beyond said stop, and means for yieldingly supporting said tube adapted to permit a movement thereof corresponding to the normal projection of said tube beyond said stop.

8. In a drilling mechanism, the combina tion with a drill chuck, a hammer piston and an anvil block interposed'between said piston and said chuck, of a longitudinally disposed tube normally adapted to extend freely a substantial distance into the bore of a hollow drill steel for supplying cleansing fluid to the latter carried by said chuck, said tube extending through and projecting beyond said anvil block, and means for supporting said tube adapted to permit a-longitudinal movement thereof equal to the projection of tube beyond said anvil block.

9. In a drilling mechanism, the combination with a drill chuck, a hammer piston and an anvil block interposed between said piston and said chuck, of a cleansing fluid supply tube extending longitudinally through said piston and terminating within said anvil block, means for rigidly supporting the rear end of said tube, a second cleansing fluid supply tube extending through said first named tube and having its forward end projecting beyond said anvil blockand normally adapted to extend freely into a hollow drill steel, and'means for supporting the rear end of said last named tube adapted to permit longitudinal movement thereof in the event of engagement by a malformed drill steel.

10. In a rock drilling mechanism, the combinati on with a cylinder having a head block, a hammer piston in said cylinder, a drill chuck, and an anvil block interposed between said piston and chuck, of a gland carried by said head block, a cleansing fluid supply tube having its rear end rigidly supported by said gland, said tube extending longitudinally through said piston and having its forward end terminating within said anvil block, a second fluid supply tube extending through said first named tube, said last named tube having its rear'end supported for longitudinal movement in said gland and its forward end projecting beyond said anvil block and normally adapted to extend freely into a hollow drill steel, a gland plug having a chamber disposed in alinement with said second tube and into which the rear end of said second tube is longitudinally movable, and

a spring in said chamber for normally press ing said second tube forwardly.

11. In a rock drllhng mechanism, the com bination with a drill chuck, a hammer piston,

and an anvil block interposed between said piston and chuck, of a yieldingly mounted tube extending through said anvil block and normally adapted to extend freely a substantial distance into the bore of a hollow drill steel. carried by said chuck for supplying cleansing fluid'thereto, the free end of said tube adapted to be moved into'said anvil block to prevent damage of the same when a drill steel is being inserted in said chuck in the event that the tube fails to register with the bore in the drill steel or of an obstruction in said bore.

12. In a rock drilling mechanism, the combination with a drill chuck, a hammer piston, and an anvil block interposed between said piston and said chuck, of a longitudinally disposed tube extending through said block and normally adapted to extend freely a'substantial distance into the bore of a hollow drill steel carried by said chuck for supplying cleansing fluid thereto,and means for supporting said tube adapted to permit longitudinal movement thereof, sufiicient to allow the free end of said tube to move into said block to prevent possible damage to the same during insertion of a drill steel in the chuck in the event that said tube fails to register with the bore in the of an obstruction in said bore.

13. In a drilling mechanism,the combination with a cylinder and piston, a cleansing drill steel or fluid supplytuhe mounted at one end for longitudinal movement in the rear end of said cylinder, the free end of said tube adapted to normally register with the bore in a drill steel during insertion of the latter and being of suflioient length to extend a substantial distanceinto said bore when the steel is in operative position, said tube adapted to move rearwardly in the event that the same fails to register with the bore of the 10 drill steel or of an obstruction in said bore. In testimony whereof I afiiX my signature.

' JAMES e. GRAHAM. 

